Britain will not support any future search and rescue operations to prevent migrants and refugees drowning in the Mediterranean, claiming they simply encourage more people to attempt the dangerous sea crossing, The Guardian reports, quoting Foreign Ministry officials.

The British refusal comes as the official Italian sea and rescue operation, Mare Nostrum, is due to end this week after contributing over the past 12 months to the rescue of an estimated 150,000 people since the Lampedusa tragedies in which 500 migrants died in October 2013.

The Italian operation will now end without a similar European search and rescue operation to replace it. The Italian authorities have said their operation, which involves a significant part of the Italian navy, is unsustainable. Despite its best efforts, more than 2,500 people are known to have drowned or gone missing in the Mediterranean since the start of the year.

Instead of the Italian operation, a limited joint EU "border protection" operation, codenamed Triton and managed by Frontex, the European border agency, is to be launched on 1 November. Crucially, it will not include search and rescue operations across the Mediterranean, just patrols within 30 miles of the Italian coast.

Human rights organisations have raised fears that more migrants and refugees will die in their attempt to reach Europe from the north African coast. The hard-pressed Italian navy will be left to mount what search and rescue operations it can. The new European operation will have only a third of the resources of the Italian operation that is being phased out, The Guardian says.

British policy was quietly spelled out in a recent House of Lords written answer by the new Foreign Office minister, Lady Anelay: "We do not support planned search and rescue operations in the Mediterranean," she said, adding that the government believed there was "an unintended 'pull factor', encouraging more migrants to attempt the dangerous sea crossing and thereby leading to more tragic and unnecessary deaths".

Anelay said: "The government believes the most effective way to prevent refugees and migrants attempting this dangerous crossing is to focus our attention on countries of origin and transit, as well as taking steps to fight the people smugglers who wilfully put lives at risk by packing migrants into unseaworthy boats."

The Home Office told the Guardian the government was not taking part in Operation Triton at present beyond providing one "debriefer" - a single immigration officer - to gather intelligence about the migrants who continue to make the dangerous journey to Italy.

The British Refugee Council chief executive, Maurice Wren, responding to the Foreign Office refusal to take part in future search and rescue operations in the Mediterranean said: "The British government seems oblivious to the fact that the world is in the grip of the greatest refugee crisis since the second world war.

"People fleeing atrocities will not stop coming if we stop throwing them life-rings; boarding a rickety boat in Libya will remain a seemingly rational decision if you're running for your life and your country is in flames. The only outcome of withdrawing help will be to witness more people needlessly and shamefully dying on Europe's doorstep.

"The answer isn't to build the walls of fortress Europe higher, it's to provide more safe and legal channels for people to access protection."